GitHub Copilot exposes two very different hook surfaces: a rich Copilot CLI stream with weak identity and derived turns, and a thin VS Code agent-hooks Preview with exact tool and agent IDs.

In this post I look at the new experimental support for DBSC provided by the Microsoft.AspNetCore.Authentication.DeviceBoundSessions package

In this post I provide an introduction to Device Bound Session Credentials, I look at how DBSC protects against session hijacking, and how the protocol works

This issue includes bits of life story, AI, C#, security, performance, Aspire, TDD, .NET and of course .NET Internals.

In this post I discuss the System.Text.Json support for unions and closed hierarchies coming in .NET 11, the decisions made, and some of the sharp edges I hit

Multiple line secrets or configuration do not work in Aspire per default. An example of this is using a PEM file for certificates. This posts shows how the multiple line configuration parameters ca…

In this post I describe the Fetch Metadata HTTP headers like Sec-Fetch-Site and Sec-Fetch-Mode which give information to a server about the context of a request

This issue includes bits of AI, Security, MS SQL, Performance, C#, HTTP and of course .NET and .NET Internals.

In this post I describe the new Cross-Site Request Forgery protection added to ASP.NET Core that uses Fetch Metadata HTTP headers instead of antiforgery tokens

In this post I describe the Fetch Metadata HTTP headers like Sec-Fetch-Site and Sec-Fetch-Mode which give information to a server about the context of a request

Using NativeAOT to write a .NET GC in C#. In this part, we add support for finalization.

This issue includes bits of AI, software development, C++, C#, diagnostics, architecture and of course .NET and .NET Internals.

In this post I describe what a close closed hierarchy is, how to create one, and discuss why you might want to

Why .NET is replacing the DAC with the cDAC data contracts, how they work locally / over a process / from a dump, and how to map the GitHub .md contracts to C# - with a from-scratch !eeheap as a worki...

in this post I take a short look at the new MoveChunks API, explore how it works, what it's for, and how the new API provides opportunities for public APIs

This is a bit of rambling from me and what I believe is a good setup for developing software together with AI tools. I believe the AI tools are good, which will help good developers produce better …

This issue includes bits of AI (too much AI), C#, software development, architecture, Windows, security, NTFS and of course .NET and .NET Internals.

In this post I discuss the support for union types released in .NET 11, how they're implemented, the choices made, and how to create your own

This week, I was updating my Aspire applications after the latest release and I ran into a deployment bug for my test deployments. I could no longer deploy the database to Azure SQL. I got the foll…

In this post I discuss the new Web Worker template available in .NET 11 for running CPU intensive tasks without blocking the UI

This issue includes bits of computer science, AI (unfortunately a lot of AI), academic papers, software development, architecture, performance, scheduling, C#, C++, .NET and .NET Internals.

In this post I show some of the new features in Git 2.54 including simple rebases with git history, config-based hooks, and stats with git repo structure

In this post I describe how to remove static byte[] allocations, even on .NET Framework, by using Span<T>, look at the associated IL, and discuss the risks

For easier access, I’ve decided to move my blog to github pages at https://chrisnas.github.io/.

In this post I describe how to create custom templates for Docker Sandboxes, so that your sandboxes start with additional tools immediately available

In this post I show how to run AI coding agents safely while still using YOLO/dangerous mode using docker sandboxes and the sbx tool

This issue includes bits (or I would rather say bytes) of AI, bits of software development, operating systems, web, diagnostics, performance, C++, C#,  and of course .NET and .NET Internals.

In this post I take a brief look at the Microsoft.Extensions.Options.Contextual package to understand what it's for, how to use it, and whether to use it or not

Polecat is now completely supported by JasperFx Software and automatically part of any existing and future support agreements through our existing plans. Polecat was released as 1.0 this past week …

Join us March 24 for a first look at Duende User Management. Learn to replace ASP.NET Identity with built-in Passkeys, MFA, and audits.

Using NativeAOT to write a .NET GC in C#. In this part, we look at what the GC must do to properly handle frozen segments, and we change the allocation strategy to make it more efficient.

🚀 I’m wrapping up my current engagement soon and starting to look for my next technical challenge. I’ll be available again starting April 10. A bit about me: • 20+ years of experience building and d...

Automatically localize DataAnnotations validation attributes in .NET - mrpmorris/AutoLocalize

In this post I describe the recent architectural changes to the NetEscapades.EnumGenerators package, which is now a metapackage, to support more scenarios

In this post I show how you can use MeterListener to listen to Instrument measurements, how to trigger Observable measurements, and how to aggregate values.

Sometimes the most convincing performance gains deserve a second look. A reminder that profiling data can be more subtle than it first appears.